Thu, 01 Aug 2013 17:25:10 -0700
Merge
1 /*
2 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
25 #ifndef SHARE_VM_OPTO_CALLGENERATOR_HPP
26 #define SHARE_VM_OPTO_CALLGENERATOR_HPP
28 #include "compiler/compileBroker.hpp"
29 #include "opto/callnode.hpp"
30 #include "opto/compile.hpp"
31 #include "opto/type.hpp"
32 #include "runtime/deoptimization.hpp"
34 //---------------------------CallGenerator-------------------------------------
35 // The subclasses of this class handle generation of ideal nodes for
36 // call sites and method entry points.
38 class CallGenerator : public ResourceObj {
39 public:
40 enum {
41 xxxunusedxxx
42 };
44 private:
45 ciMethod* _method; // The method being called.
47 protected:
48 CallGenerator(ciMethod* method) : _method(method) {}
50 public:
51 // Accessors
52 ciMethod* method() const { return _method; }
54 // is_inline: At least some code implementing the method is copied here.
55 virtual bool is_inline() const { return false; }
56 // is_intrinsic: There's a method-specific way of generating the inline code.
57 virtual bool is_intrinsic() const { return false; }
58 // is_parse: Bytecodes implementing the specific method are copied here.
59 virtual bool is_parse() const { return false; }
60 // is_virtual: The call uses the receiver type to select or check the method.
61 virtual bool is_virtual() const { return false; }
62 // is_deferred: The decision whether to inline or not is deferred.
63 virtual bool is_deferred() const { return false; }
64 // is_predicted: Uses an explicit check against a predicted type.
65 virtual bool is_predicted() const { return false; }
66 // is_trap: Does not return to the caller. (E.g., uncommon trap.)
67 virtual bool is_trap() const { return false; }
69 // is_late_inline: supports conversion of call into an inline
70 virtual bool is_late_inline() const { return false; }
71 // same but for method handle calls
72 virtual bool is_mh_late_inline() const { return false; }
74 // for method handle calls: have we tried inlinining the call already?
75 virtual bool already_attempted() const { ShouldNotReachHere(); return false; }
77 // Replace the call with an inline version of the code
78 virtual void do_late_inline() { ShouldNotReachHere(); }
80 virtual CallStaticJavaNode* call_node() const { ShouldNotReachHere(); return NULL; }
82 // Note: It is possible for a CG to be both inline and virtual.
83 // (The hashCode intrinsic does a vtable check and an inlined fast path.)
85 // Utilities:
86 const TypeFunc* tf() const;
88 // The given jvms has state and arguments for a call to my method.
89 // Edges after jvms->argoff() carry all (pre-popped) argument values.
90 //
91 // Update the map with state and return values (if any) and return it.
92 // The return values (0, 1, or 2) must be pushed on the map's stack,
93 // and the sp of the jvms incremented accordingly.
94 //
95 // The jvms is returned on success. Alternatively, a copy of the
96 // given jvms, suitably updated, may be returned, in which case the
97 // caller should discard the original jvms.
98 //
99 // The non-Parm edges of the returned map will contain updated global state,
100 // and one or two edges before jvms->sp() will carry any return values.
101 // Other map edges may contain locals or monitors, and should not
102 // be changed in meaning.
103 //
104 // If the call traps, the returned map must have a control edge of top.
105 // If the call can throw, the returned map must report has_exceptions().
106 //
107 // If the result is NULL, it means that this CallGenerator was unable
108 // to handle the given call, and another CallGenerator should be consulted.
109 virtual JVMState* generate(JVMState* jvms) = 0;
111 // How to generate a call site that is inlined:
112 static CallGenerator* for_inline(ciMethod* m, float expected_uses = -1);
113 // How to generate code for an on-stack replacement handler.
114 static CallGenerator* for_osr(ciMethod* m, int osr_bci);
116 // How to generate vanilla out-of-line call sites:
117 static CallGenerator* for_direct_call(ciMethod* m, bool separate_io_projs = false); // static, special
118 static CallGenerator* for_virtual_call(ciMethod* m, int vtable_index); // virtual, interface
119 static CallGenerator* for_dynamic_call(ciMethod* m); // invokedynamic
121 static CallGenerator* for_method_handle_call( JVMState* jvms, ciMethod* caller, ciMethod* callee, bool delayed_forbidden);
122 static CallGenerator* for_method_handle_inline(JVMState* jvms, ciMethod* caller, ciMethod* callee, bool& input_not_const);
124 // How to generate a replace a direct call with an inline version
125 static CallGenerator* for_late_inline(ciMethod* m, CallGenerator* inline_cg);
126 static CallGenerator* for_mh_late_inline(ciMethod* caller, ciMethod* callee, bool input_not_const);
127 static CallGenerator* for_string_late_inline(ciMethod* m, CallGenerator* inline_cg);
128 static CallGenerator* for_boxing_late_inline(ciMethod* m, CallGenerator* inline_cg);
130 // How to make a call but defer the decision whether to inline or not.
131 static CallGenerator* for_warm_call(WarmCallInfo* ci,
132 CallGenerator* if_cold,
133 CallGenerator* if_hot);
135 // How to make a call that optimistically assumes a receiver type:
136 static CallGenerator* for_predicted_call(ciKlass* predicted_receiver,
137 CallGenerator* if_missed,
138 CallGenerator* if_hit,
139 float hit_prob);
141 // How to make a call that optimistically assumes a MethodHandle target:
142 static CallGenerator* for_predicted_dynamic_call(ciMethodHandle* predicted_method_handle,
143 CallGenerator* if_missed,
144 CallGenerator* if_hit,
145 float hit_prob);
147 // How to make a call that gives up and goes back to the interpreter:
148 static CallGenerator* for_uncommon_trap(ciMethod* m,
149 Deoptimization::DeoptReason reason,
150 Deoptimization::DeoptAction action);
152 // Registry for intrinsics:
153 static CallGenerator* for_intrinsic(ciMethod* m);
154 static void register_intrinsic(ciMethod* m, CallGenerator* cg);
155 static CallGenerator* for_predicted_intrinsic(CallGenerator* intrinsic,
156 CallGenerator* cg);
157 virtual Node* generate_predicate(JVMState* jvms) { return NULL; };
159 virtual void print_inlining_late(const char* msg) { ShouldNotReachHere(); }
161 static void print_inlining(Compile* C, ciMethod* callee, int inline_level, int bci, const char* msg) {
162 if (PrintInlining)
163 C->print_inlining(callee, inline_level, bci, msg);
164 }
165 };
168 //------------------------InlineCallGenerator----------------------------------
169 class InlineCallGenerator : public CallGenerator {
170 protected:
171 InlineCallGenerator(ciMethod* method) : CallGenerator(method) {}
173 public:
174 virtual bool is_inline() const { return true; }
175 };
178 //---------------------------WarmCallInfo--------------------------------------
179 // A struct to collect information about a given call site.
180 // Helps sort call sites into "hot", "medium", and "cold".
181 // Participates in the queueing of "medium" call sites for possible inlining.
182 class WarmCallInfo : public ResourceObj {
183 private:
185 CallNode* _call; // The CallNode which may be inlined.
186 CallGenerator* _hot_cg;// CG for expanding the call node
188 // These are the metrics we use to evaluate call sites:
190 float _count; // How often do we expect to reach this site?
191 float _profit; // How much time do we expect to save by inlining?
192 float _work; // How long do we expect the average call to take?
193 float _size; // How big do we expect the inlined code to be?
195 float _heat; // Combined score inducing total order on call sites.
196 WarmCallInfo* _next; // Next cooler call info in pending queue.
198 // Count is the number of times this call site is expected to be executed.
199 // Large count is favorable for inlining, because the extra compilation
200 // work will be amortized more completely.
202 // Profit is a rough measure of the amount of time we expect to save
203 // per execution of this site if we inline it. (1.0 == call overhead)
204 // Large profit favors inlining. Negative profit disables inlining.
206 // Work is a rough measure of the amount of time a typical out-of-line
207 // call from this site is expected to take. (1.0 == call, no-op, return)
208 // Small work is somewhat favorable for inlining, since methods with
209 // short "hot" traces are more likely to inline smoothly.
211 // Size is the number of graph nodes we expect this method to produce,
212 // not counting the inlining of any further warm calls it may include.
213 // Small size favors inlining, since small methods are more likely to
214 // inline smoothly. The size is estimated by examining the native code
215 // if available. The method bytecodes are also examined, assuming
216 // empirically observed node counts for each kind of bytecode.
218 // Heat is the combined "goodness" of a site's inlining. If we were
219 // omniscient, it would be the difference of two sums of future execution
220 // times of code emitted for this site (amortized across multiple sites if
221 // sharing applies). The two sums are for versions of this call site with
222 // and without inlining.
224 // We approximate this mythical quantity by playing with averages,
225 // rough estimates, and assumptions that history repeats itself.
226 // The basic formula count * profit is heuristically adjusted
227 // by looking at the expected compilation and execution times of
228 // of the inlined call.
230 // Note: Some of these metrics may not be present in the final product,
231 // but exist in development builds to experiment with inline policy tuning.
233 // This heuristic framework does not model well the very significant
234 // effects of multiple-level inlining. It is possible to see no immediate
235 // profit from inlining X->Y, but to get great profit from a subsequent
236 // inlining X->Y->Z.
238 // This framework does not take well into account the problem of N**2 code
239 // size in a clique of mutually inlinable methods.
241 WarmCallInfo* next() const { return _next; }
242 void set_next(WarmCallInfo* n) { _next = n; }
244 static WarmCallInfo _always_hot;
245 static WarmCallInfo _always_cold;
247 // Constructor intitialization of always_hot and always_cold
248 WarmCallInfo(float c, float p, float w, float s) {
249 _call = NULL;
250 _hot_cg = NULL;
251 _next = NULL;
252 _count = c;
253 _profit = p;
254 _work = w;
255 _size = s;
256 _heat = 0;
257 }
259 public:
260 // Because WarmInfo objects live over the entire lifetime of the
261 // Compile object, they are allocated into the comp_arena, which
262 // does not get resource marked or reset during the compile process
263 void *operator new( size_t x, Compile* C ) { return C->comp_arena()->Amalloc(x); }
264 void operator delete( void * ) { } // fast deallocation
266 static WarmCallInfo* always_hot();
267 static WarmCallInfo* always_cold();
269 WarmCallInfo() {
270 _call = NULL;
271 _hot_cg = NULL;
272 _next = NULL;
273 _count = _profit = _work = _size = _heat = 0;
274 }
276 CallNode* call() const { return _call; }
277 float count() const { return _count; }
278 float size() const { return _size; }
279 float work() const { return _work; }
280 float profit() const { return _profit; }
281 float heat() const { return _heat; }
283 void set_count(float x) { _count = x; }
284 void set_size(float x) { _size = x; }
285 void set_work(float x) { _work = x; }
286 void set_profit(float x) { _profit = x; }
287 void set_heat(float x) { _heat = x; }
289 // Load initial heuristics from profiles, etc.
290 // The heuristics can be tweaked further by the caller.
291 void init(JVMState* call_site, ciMethod* call_method, ciCallProfile& profile, float prof_factor);
293 static float MAX_VALUE() { return +1.0e10; }
294 static float MIN_VALUE() { return -1.0e10; }
296 float compute_heat() const;
298 void set_call(CallNode* call) { _call = call; }
299 void set_hot_cg(CallGenerator* cg) { _hot_cg = cg; }
301 // Do not queue very hot or very cold calls.
302 // Make very cold ones out of line immediately.
303 // Inline very hot ones immediately.
304 // These queries apply various tunable limits
305 // to the above metrics in a systematic way.
306 // Test for coldness before testing for hotness.
307 bool is_cold() const;
308 bool is_hot() const;
310 // Force a warm call to be hot. This worklists the call node for inlining.
311 void make_hot();
313 // Force a warm call to be cold. This worklists the call node for out-of-lining.
314 void make_cold();
316 // A reproducible total ordering, in which heat is the major key.
317 bool warmer_than(WarmCallInfo* that);
319 // List management. These methods are called with the list head,
320 // and return the new list head, inserting or removing the receiver.
321 WarmCallInfo* insert_into(WarmCallInfo* head);
322 WarmCallInfo* remove_from(WarmCallInfo* head);
324 #ifndef PRODUCT
325 void print() const;
326 void print_all() const;
327 int count_all() const;
328 #endif
329 };
331 #endif // SHARE_VM_OPTO_CALLGENERATOR_HPP